This invention relates to the use of poly(epsilon caprolactone) homopolymers taken alone or taken in admixture with other polymers for use as controlled release devices for controlled release of diagnostic materials and/or insect repellents and/or animal repellents and/or aroma augmenting or enhancing compositions and/or pheromones, which polycaprolactones are defined according to the structure: ##STR2## wherein n varies from about 500 up to about 1,200 with the proviso that the average "n" varies from about 600 up to about 800.
The use of polycaprolactones in controlled release situations is known in the prior art. Poly(epsilon caprolactone) as well as copolymers of epsilon decalactone and epsilon caprolactone are disclosed for their utilities as biodegradable polymers for sustained drug delivery in "Contemporary Topics In Polymer Science", Vol. 2, Pearce, et al, Plenum Press, New York, 1977, at page 271. The system for controlled release of drugs into an aqueous system, e.g., in vivo in mammalian species is different in kind from a system whereby there occurs a controlled release of diagnostic compositions or perfume compositions or perfume materials and/or animal repellents and/or insect repellents and/or pheromones from such polycaprolactones or mixtures of polycaprolactones with other polymers into a gaseous environment, e.g., the atmosphere surrounding such polymer systems.
An ever increasing requirement in the medical diagnosis field and in the perfume, animal repellent and insect repellent industries exists for a slow controlled release device for slowly and controllably releasing diagnostic compositions for diagnosing physiological malfunctions or aberrations in mammalian species, animal repellents and/or insect repellents and/or perfume materials and/or pheromones into a gaseous environment in order to aid in the diagnosis of such malfunctions or aberrations and/or to aesthetically scent the said environment and/or in order to repel insects and/or in order to repel mammalian species, e.g., deer, coyote, dogs and the like.
Slow release polymers containing perfumes are well known in the prior art. Thus, United Kingdom patent specification No. 1,589,201 (the specification for which is incorporated by reference herein) assigned to Hercules Inc. discloses a thermoplastic resin body consisting of a thermoplastic copolymer of ethylene and 6-60 weight percent of a polar vinyl monomer selected from the group consisting of vinyl acetate, methyl acrylate, ethyl acrylate, butyl acrylate and acrylic acid wherein the perfumed resin body is suitable for the preparation of shaped objects from which perfume odor emanates over a prolonged period at a stable level.
U.S. Pat. No. 3,505,432 (the specification for which is incorporated by reference herein) discloses a method of scenting a polyolefin which comprises:
(a) mixing a first amount of liquid polyolefin, e.g., polyethylene or polypropylene with a relatively large amount of scent-imparting material to form a flowable mass;
(b) forming drops from said mass and causing substantially instantaneous solidification of said drops into polyolefin pellets having a relatively large amount of scent-imparting material imprisoned therein;
(c) melting said pellets with a second amount of said polyolefin, said second amount being larger than said first amount; and
(d) solidifying the melt of (c).
The method of adding functional fluids to poly(epsilon caprolactone) homopolymers or mixtures of poly(epsilon caprolactone) hompolymers and other polymers is different in kind from the techniques disclosed in U.S. Pat. No. 3,505,432 in view of the physical properties of the poly(epsilon caprolactone) homopolymers. Thus, the use of an extruder, a jet molding apparatus or the like is a much more practical way of producing a mixture of the functional fluid and poly(epsilon caprolactone) homopolymer than the method of U.S. Pat. No. 3,505,432.
U.S. Pat. No,. 4,247,498 issued on Jan. 27, 1981 (the specification for which is incorporated by reference herein) discloses microporous polymers which are capable of containing volatile substances such as perfumes and the like in forms ranging from films to blocks in intricate shapes from synthetic thermoplastic polymers such as olefinic, condensation polymers. In one embodiment of U.S. Pat. No. 4,247,498 the microporous polymers are characterized by relatively homogenous three-dimensional cellular structures having cells connected by pores of smaller dimension. Also disclosed in U.S. Pat. No. 4,247,498 is a process for making microporous polymers from such thermoplastic polymers by heating a mixture of the polymer and a compatible liquid (e.g., a perfume substance or the like) to form a homogeneous solution, cooling said solution under non-equilibrium thermodynamic conditions to initiate liquid-liquid phase separation, and continuing said cooling until the mixture achieves substantial handling strength. Also disclosed in said U.S. Pat. No. 4,247,498 are microporous polymer products which contain relatively large amounts of such functionally useful fluids as perfume compositions and behave as solids. U.S. Pat. No. 4,247,498 however, does not disclose the unexpected and unobvious advantages of polycaprolactone homopolymers or mixtures of such polycaprolactone homopolymers and other polymers such as polyethylene, polypropylene and copolymers of polyethylene and polyvinyl acetate when admixed with materials which are controllably releasable therefrom including diagnostic compositions or aroma augmenting or enhancing materials such as perfume compositions, animal repellents and pheromones and insect repellent compositions.
U.S. Pat. No. 4,156,067 issued on May 22, 1979 (the specification for which is incorporated by reference herein) discloses polyurethane polymers characterized by a molecular weight of above 6,000 and having lactone groups and hydroxyl groups in the polymer backbone being prepared by reacting a mixture of polyols, a polyfunctional lactone (e.g., epsilon caprolactone) and a polyfunctional isocyanate proportioned so as to provide certain desired polymer properties. It is indicated in said U.S. Pat. No. 4,156,067 that the product is soluble in alkaline solutions and may be used for light sensitive photographic layers on films, paper or glass; in drug delivery systems, as burn dressings, in body implants such as vascular prosthesis, in molding compositions, and in the manufacture of catheters as well as in delivery of perfume compositions in a slow release manner. It is further indicated in said U.S. Pat. No. 4,156,067 that the water absorptivity of the polyurethane/lactone polymers is above 10%, preferably in the range of about 20% to 60%, and these polymers may range in their physical properties from rigid solids to completely gel-like high water absorptive polymers. It is further indicated in said U.S. Pat. No. 4,156,067 that the polymers provide a leachable substrate wherein the leaching agent may be water, gases, alcohols, esters and body fluids, e.g., animal or human. The polymer system of U.S. Pat. No. 4,156,067 is different in kind from that of our invention. Nothing in said U.S. Pat. No. 4,156,067 however, discloses the unexpected and unobvious advantages of the homopolymers of epsilon caprolactone in their uses as carriers for effecting diagnosis of physiological or psychological functions or malfunctions in mammalian species, or for augmenting or enhancing the aroma of perfume compositions or perfumed articles; and/or as insect repellents and/or as animal repellents.
U.S. Pat. No. 4,156,067 further discloses a solution of perfume and a hydrophilic polyurethane polymer in a non-toxic solvent wherein said polyurethane polymer comprises the reaction product:
(A) one or more diols having an equivalent weight in the range of from about 100 to about 3,000, selected from the group consisting of:
(a) diethylene glycol, PA1 (b) long chain polyoxyalkylene diols, PA1 (c) linear polyester diols derived from the condensation of one or more diols with one or more dibasic acids, and PA1 (d) the reaction product of one or more alkylene diols with a difunctional linear polyester derived from the condensation of one or more diols with one or more dibasic acids;
(B) a polyfunctional lactone having the formula ##STR3## wherein R.sub.1 is a monovalent radical selected from the group consisting of --H, --CHNH.sub.2, --SO.sub.2 CH.sub.3, --CHOHCOOH, and --(CHOH).sub.n CH.sub.2 OH; n being an integer from 0 to 5; and R.sub.2 is a divalent radical --(CHOH).sub.m --; m being an integer from 2 to 10; and ethers derived from said lactones; and
(C) a urethane precursor selected from the group consisting of organic polyisocyanates and nitrile carbonates.
U.S. Pat. No. 4,018,729 issued on Apr. 19, 1977 (the specification for which is incorporated by reference herein) as well as U.S. Pat. No. 3,992,336 issued on Oct. 1, 1974 (the specification for which is incorporated by reference herein) discloses articles for conditioning hair which are fabricated by blending water soluble polymers with water insoluble polymers (e.g., poly(epsilon caprolactone) to form interpenetrating networks so that the water soluble polymer can be extracted from the article when wet, or when brought in contact with wet hair. Nothing in said U.S. Pat. No. 4,018,729 discloses the concept of the instant invention.
In general, nothing in the prior art discloses the use of the polycaprolactone homopolymers as defined, supra, as devices for controlled release into a gaseous environment of diagnostic compositions, insect repellents, animal repellents, pheromones and perfume materials for use in perfume compositions, colognes and perfumed articles, e.g., solid or liquid anionic, cationic, nonionic or zwitterionic detergents, fabric softener articles and the like.